The proposed work will continue the ongoing studies of glutathione metabolism in the ocular lens, and will concentrate upon the following areas: The control mechanisms of gamma-glutamylcysteine synthetase, study of the isolated enzyme, glutathione peroxidase, study of possible effects of various cataractogenic agents upon the activity of several enzymes which metabolize glutathione, study of the effects, if any, of ultraviolet light upon glutathione metabolism in the lens, and assay of the activity of certain enzymes of the glutathione metabolic scheme in the human lens.